urn:nasa:pds:a15sws_solar_wind_28s_1hr 1.0 1.23.0.0 Product_Bundle 2025 10.17189/zn9j-er37 This data set contains daily tables of time ordered, 28-second-resolution plasma parameters, mainly of the solar wind, as observed on the Moon at the Apollo 15 ALSEP site by the Apollo 15 Solar Wind Spectrometer (SWS) from 31 July 1971 through 30 June 1972. This data set also contains tables of time ordered, hourly averaged plasma parameters, mainly of the solar wind, as observed on the Moon at the Apollo 15 ALSEP site by the Apollo 15 Solar Wind Spectrometer (SWS) from 31 July 1971 through 30 June 1972. David R. Williams National Space Science Data Center Conway Snyder NASA Jet Propulsion Laboratory Marcia Neugebauer NASA Jet Propulsion Laboratory Douglas Clay NASA Jet Propulsion Laboratory H. K. Hill D. Han Producer Abigail Knight Washington University in St. Louis 2025-09-26 1.0 Initial bundle. 1971-07-31T19:30:00Z 1972-06-30T18:14:35Z Science Calibrated The 28-second SWS data tables are in fixed-width ASCII format. There is one table for each daily set of SWS measurements. During the local lunar night there was no solar wind signal so there are data gaps of about 15 days each lunation. Each daily table contains a sequence of plasma measurements made every 28.1 seconds. Each record in a table provides the time of a measurement, proton density, alpha-to-proton ratio, proton bulk speed, and angle of flow. Each record identifies the Faraday cup on the side of the instrument (one of six) that measured the most charge. The measured charge of this cup, the adjacent side cups, and the vertical (top) cup are included in each record as well as the most probable thermal speed, and various housekeeping and fit parameters relating to the reliability of the calculated plasma parameters. Note that a value of 99.0 in Column 14, the Percentage Error in Fitting Program, indicates the fit was bad and thus all computed plasma parameters in that row are invalid. These data tables were converted from the CDF format which was created from the original binary data set PSFP-00113 by the NSSDC as part of the Lunar Data Restoration project. The original tapes were written in BCD format on a UNIVAC 1108 computer. See Clay, et al. (1972) [CLAYETAL1972], Goldstein, et al. (1973) [GOLDSTEINETAL1973] and Clay, et al. (1975) [CLAYETAL1975] for more information about the SWS plasma data from Apollo 15. The NSSDC restored all data that were available in the original binary data set. There are gaps within the tables in this PDS data set because there were no data available at the NSSDC for those periods of time. The hourly averaged SWS data tables are in fixed-width ASCII format. There is one table for each year the SWS recorded data. During the local lunar night there was no solar wind signal so there are data gaps of about 15 days each lunation. Each table provides four sets of computed hourly parameters using as input data: (1) all fine-time scale parameters (FTSP), (2) all FTSP computed from spectra with small root-mean-square (RMS) error on curve fitting and thermal speeds less than one-half the bulk velocity, (3) all FTSP computed from spectra that satisfy the requirements of criterion 2 as well as having only one flow angle that can be directly measured, and (4) all FTSP computed from spectra that satisfy the requirements of criterion 2 as well as having both flow angles directly measurable. Contained in each of the four sets of averages are the proton density, alpha-to-proton ratio, bulk speed, angle of flow, number of spectra, and RMS deviations of each average. These data tables were converted from the CDF format which was created from the original binary data set PSFP-00084 by the NSSDC as part of the Lunar Data Restoration project. The original tapes were written in BCD format on a UNIVAC 1108 computer. See Clay, et al. (1972), Goldstein, et al. (1973) and Clay, et al. (1975) for more information about the SWS plasma data from Apollo 15. This data set description was provided by the NSSDC. Apollo 15 Mission urn:nasa:pds:context:investigation:mission.apollo_15 bundle_to_investigation The Apollo 15 Lunar Surface Experiments Package Host urn:nasa:pds:context:instrument_host:spacecraft.a15a is_instrument_host Apollo 15 Lunar Surface Experiments Package Solar Wind Spectrometer Instrument urn:nasa:pds:context:instrument:sws.a15a is_instrument Moon Satellite urn:nasa:pds:context:target:satellite.earth.moon bundle_to_target Clay, D.R., B.E. Goldstein, M. Neugebauer and C.W. Snyder, Apollo 15 - solar wind spectrometer experiment, Apollo 15 Preliminary Science Report, SP-289, pages 10-1 to 10-7, published by NASA, Washington, DC, 1972. Goldstein, B.E., D.R. Clay, C.W. Snyder and M. Neugebauer, ALSEP solar wind spectrometer plasma data as observed at the Apollo 12 and 15 landing sites, Jet Propulsion Laboratory, Contract NAS7-100, 1973. 10.1029/JA080i013p01751 Clay, D.R., B.E. Goldstein, M. Neugebauer and C.W. Snyder, Lunar surface solar wind observations at the Apollo 12 and Apollo 15 sites, Journal of Geophysical Research, 80, 1751-1760, 1975. Archive readme.txt 3263 0 7-Bit ASCII Text Brief overview of this bundle. Carriage-Return Line-Feed urn:nasa:pds:a15sws_solar_wind_28s_1hr:data Primary bundle_has_data_collection urn:nasa:pds:a15sws_solar_wind_28s_1hr:document Primary bundle_has_document_collection